A microsphere of PuN



Novel fuel for today’s and tomorrow’s reactors

​At the heart of a nuclear reactor resides its fuel. The chemical composition of the nuclear fuel affects the performance of several key properties important for the overall operation and safety performance of the reactor. Marcus Hedberg has spent the last five years manufacturing and characterizing nitride fuels, an alternative to the oxide fuels used in today’s light water reactors. But the nitride fuels can also be an attractive fuel for liquid metal cooled reactors envisioned for the fourth generation nuclear power systems. We asked Marcus some questions about his research.

Which application do you find most interesting for your nitrides?
The non-uranium containing fuels I have been working with mainly aims for use in potential future non-breeding reactor applications. This means that the kinds of fuels I have produced aims at energy production without simultaneously generating new fissile materials.

You manufactured the world’s first pure plutonium nitride pellet – why?
The material as such has been produced before on a few occasions for example in Japan. Production of final fuel pellets are however fairly unstudied. This is because pure PuN is not generally envisioned as fuel but rather PuN diluted using a second material such as uranium nitride (UN) or zirconium nitride (ZrN) for example. It is however of interest to study pure PuN as a reference to have knowledge about how the individual pure materials behave during different production steps and what their properties are.

The use of plutonium-containing fuels indicates that some recycling of spent uranium fuel is envisioned. What is your view on nuclear fuel recycling?
The material taken out of a commercial reactor today still contains very large amounts of material suitable for energy production, as well as long lived trans-uranic actinides requiring long final storage time. Recycling of used nuclear fuel could potentially reduce the required storage time and allow for more electricity production at the same time. So recycling sounds like it is worth aiming for.

You are now going to work partly with the EU-project BIFROST – could you tell us a few words about that project and your role in it?
BIFROST will be a cross disciplinary project that will investigate amongst other production, recovery and safety features of various kinds of advanced nuclear fuels. My contribution will concern the safety aspects such as potential interactions between (U,Pu)N fuels and molten lead coolant.


Marcus Hedberg will defend his thesis titled “Production and Characterization of ZrN and PuN Materials for Nuclear Fuel Applications” on 2016-10-28. We wish him the best of luck!

Page manager Published: Fri 30 Sep 2016.